The title that the painting has today was not decided by Constable. Instead, the artist always referred to its work as "The Drinking Boy". It is because of the subscribers that showed the picture to the National Gallery and simply called it "The Cornfield" if the picture took the name it still has today.
The landscape depicted departs from Constable's usual river scene and instead delineates a path through a wood leading to a cornfield. There is some water in the scene, but its presence is subtle and only confined to a corner of the painting.
Green is the predominant and almost omnipresent color, it covers over a half of the entire scene with its various shades and creates a frame around the distant fields. Everything that is part of this frame has a shade of green: all the sheep seem to hide and fade away in green shadows, there's green in the tree trunks, in the hills and in the trees in the background.
The only element that overcomes the green film and that catches the attention of the viewer almost immediately is the little boy dressed in a bright red shirt in the lower left corner of the scene.
He has temporarily abandoned his sheep to his dog and is crouching down on his stomach to see a little creek and maybe drink some water from it.
All around him the sun is shining, the land is bright and clear, the trees have bright green leaves, the clouds seem to be slowly moving across the sky, pushed forward by a gentle wind that also caresses the treetops. Everything looks completely perfect.
We get a sense of calm and peace from this bucolic scenery, and that's mostly because of colors. Thanks to the bright yellow of the fields and the clear white of the clouds someone that views the scene is immediately carried in something that feels like a daydream.
Even if Constable painted the scene with a great focus towards colors and harmony of shapes, the impression that it gives is to depict an idyllic "spot of time", a unique glimpse that will never come back again. This was John Constable's main intention: to show humans and nature in a moment of time.